Electronic devices, and specifically portable electronic devices, rely on power adapters for operating from the power mains and for charging the batteries of the devices. Different adapters are used for different devices depending on the type of device, the device power requirements and the country/countries in which the device is sold/used. Along with the different types of devices, adapters have been designed and configured to operate in different ways. For instance, various adapters include the ability to rotate or fold the prongs to increase the flexibility of uses for the adapter. Yet, the physical structure used to provide this functionality varies widely. Various examples are provided below.
U.S. Design Pat. D.308,962 shows the ornamental design of an electrical adapter plug, with the prongs of the plug capable of being adjusted about a pivot point. U.S. Design Pat. D.408,786 shows the ornamental design for a C7 connector. The prongs of the connector move along a single axis between an extended position and a folded position—the prongs folding into the body of the connector. However, the motion of the prongs is not about the face of the plug.
U.S. Pat. No. 5,420,493 is reputed to be owned by APPLE and teaches a duck head socket adapter. The duck head socket adapter attaches to an AC adapter and battery charger for a portable system. The duck head socket adapter is static and none of its parts move linearly or swivel. U.S. Pat. No. 5,616,051 is also reputed to be owned by APPLE and teaches an AC adapter having prongs that rotate along a pivot to enable the prongs to fold into a recess in the device. This feature is used for storage when the prongs are not being used, as illustrated in FIGS. 1 and 2. It also noted that the rotation of the prongs is not about the face of the adapter.
U.S. Pat. No. 5,658,152 teaches a plug having a female plug plugging into an adapter and a male plug plugging into a receptacle with the female plug and the male plugs rotating 180 degrees with respect to each other. A series of notches and dimples are used to maintain electrical contact between the female plug and the male plug during rotation.
U.S. Pat. No. 6,821,134 teaches a rotatable plug that rotates parallel to the face of the plug. The patent teaches that each prong is connected to a conductive terminal, and the conductive terminal itself is connected to a conductive wire. However, the conductive wires are never shown in any of the figures. In addition, the conductive wires do not serve a role in implementing or enabling the rotation of the face of the plug.
U.S. Pat. No. 7,497,707 teaches a C7 connector, with the prongs of the connector rotating to enable the prongs to fold into the body of the connector. The patent describes a complex arrangement of interlocking connecting elements that maintain the electrical connection when the prongs are rotated.
U.S. Pat. No. 7,573,159 teaches an APPLE duck head C7 power adapter. The prongs are moveable along an axis for enabling the prongs to be folded into the body of adapter or to be extended, but the prongs do not rotate about the face of the plug. U.S. Pat. No. 7,575,436 teaches an electrical plug adapter with a rotating cap. The patent describes the use of rotary contacts to maintain the electrical connection with the prongs of the plug.
U.S. Pat. No. 7,658,625 teaches an AC power adapter that includes prongs that swivel about the body of the adapter and that also fold into the body of the adapter for storage. U.S. Pat. No. 7,740,484 teaches a rotating receptacle that uses ring-shaped contact regions to maintain continuously electrical contact with the conductor terminals of the receptacle.
A large number of the references disclosed herein teach connectors whose prongs move linearly or rotate between an extended position and a recessed position (the prongs folded into the body of the connector). Numerous other references teach swiveling of the plug about the face of the plug, but these references either do not disclose how electrical contact is maintained with the prongs of the plug or teach complicated designs, involving numerous static and moving parts, to ensure that electrical connection is maintained even as the plug is rotated. These complicated designs taught by the relevant references increase manufacturing costs due to the increased complexity of assembly. In addition, the more parts involved in a design, the higher the probability that one of those parts will malfunction. It is desirable to have a C7 power adapter with a simple, less complicated design that decreases the number of parts needed to implement rotation of the prongs of the plug while maintaining an electrical connection.